A motor generates power for driving in eco-friendly vehicles such as an electric vehicle (EV) and a plug-in hybrid vehicle (PHEV). Such a motor is connected to an inverter and generates torque using a 3-phase current from the inverter. The inverter controls the 3-phase current to control motor torque, and generally, the 3-phase current and the position information of the rotor of the motor are obtained for current control by a sensor.
The position sensor for the rotor of the motor is disposed in the motor and is connected to the inverter through an external signal wiring. When a wiring connector is not normally fastened or a motor current is abnormally controlled due to distortion of rotor position information by disconnection or a short circuit, so undesired driving force may be generated. Accordingly, it is generally possible to stop inverter current control when there is a problem, using an error logic for a rotor position sensor, but when a problem occurs during driving, a driver cannot control the vehicle as he/she intends, so safety of the driver is not secured.
That is, according to the related art, an inverter stops motor current control when a problem of a rotor position sensor of a motor is sensed, so that power supply is stopped in an EV without a separate power source, so the vehicle has to be stopped. Therefore, when the problem described above occurs while a vehicle is driven, a driver cannot control the vehicle as intended, and therefore safety of the driver is not secured.